Cigarette-smoke- and age-dependent oxidative stress effects in rats

Abstract

Oxidative stress is a basic mechanism involved in both ageand smoking-related diseases. To test whether smoking affects young, old, and calorie-restricted organisms to the same extent, we assessed oxidative stress parameters in the lung, heart, and liver of male Fischer 344 rats (4 months old and 19-22 months old) exposed to air or cigarette mainstream smoke. Smoke-related effects were seen for parameters of DNA damage, lipid peroxidation, protein oxidation, and glycoxidation. No smoke-related effects were observed for DNA damage in the lung and heart (Comet assay) and for malondialdehyde in the lung. The old rats showed higher smoke-related responses than the young rats for 8-hydroxy-desoxyguanosine (8-OHdG) in the heart and liver, DNA damage in the liver, and protein carbonyls in the lung; however, there was little evidence for an overadditive effect of smoking on aging. Caloric restriction, which is known to retard aging effects, also had little impact on smoke-related oxidative changes.